Method for utilizing short sticks of carbon



May 26, 1959 A. E. NARLOCK METHOD FOR UTILIZING SHORT STICKS OF CARBON Filed Oct. 8. 1954 ATTORNEYS United States Patent UTILIZING SHORT STICKS OF CARBON METHOD FOR The instant invention relates to a method for re-working and utilizing short lengths of stick carbon so that they may be completely burned.

Sticks of carbon such as used in motion picture projecting machines, usually burn to about one-third of the length of the new stick, after which the remaining length becomes unuseable due to sputtering and breaking of the electric arc; consequently, these short lengths are usually discarded as waste product and new long sticks substituted each time.

Carbon sticks of the nature used in projecting machines are quite expensive, and the accumulation of short pieces resulting from each days run will, if salvaged, represent a worthwhile saving. Therefore, the prime object of the present invention is to provide a means and method whereby these short, unburned portions of -the carbon sticks can be held, bored and mounted on a metal rod or holder of predetermined length, so that the rod holder and bored carbon stick, when assembled, are approximately the same length as a new stick or carbon, the short carbon end of the stick being burned in exactly the same manner as are the new sticks, thus eliminating practically all of the wastage above referred to.

Another object is to design a method which accommodates standard carbon sticks of various diameters without any adjustment whatsoever, except actuation of the clamping means.

With the above and other objects in view, the present invention consists in the combination and arrangement of parts, hereinafter more fully described, illustrated in the accompanying drawing, and more particularly pointed out in the appended claim, it being understood that changes may be made in the form, size, proportion, and minor details of construction, without departing from the spirit or sacrificing any of the advantages of the invention.

In the drawing:

Fig. 1 is a side elevational view of my carbon clamping means showing a stick of carbon clamped in position in the device and a hand drill in position to longitudinally bore the one end thereof.

Fig. 2 is a top plan view.

Fig. 3 is a transverse sectional view taken on the line 3--3 of Fig. 2.

Fig. 4 is an elevational view of an assembled sectional carbon and holder, the carbon being broken away to illustrate the connection.

Carbon sticks as used in conventional projection machines are about 22 inches long, and in use, will burn down to lengths of approximately 8 inches, after which they begin to sputter, arc, etc., so that the picture projection is very unsatisfactory. These short 8 inch lengths represent about 35% of the cost of the original carbon sticks and make up a material saving if properly salvaged.

Referring now to the accompanying drawing in which I have shown one embodiment of my invention, the device can be formed of any desired material and includes 2,887,769- Patented May 26, 1959 a metal base 5 formed with laterally projecting flanges 6 on the lower face thereof and screw openings 7 are provided in said flanges to accommodate screws (not shown) so that the device may be fastened to a table or other support (not shown) in the conventional manner.

The upper face of the block has a V-shaped groove 8 extending the full length thereof, and an L-shaped clamp member 9 is secured to the side wall of the block equidistant from the ends in any approved manner, the leg 10 overhanging the groove 8 and a centrally disposed, threaded member 11 is mounted in a threaded opening 12 provided in said leg for engaging the carbon stick C. A transversely disposed pin 14 is mounted in the upper end of the member 11 to facilitate easy manipulation of the screw member, the end of the pin engaging and clamping the short length of carbon C which has been laid in the groove 8 preparatory to boring.

The carbon must be longitudinally bored, and this I have accomplished by means of a metal rod 15 which is of the same diameter as the carbon C, one end being squared as at 16 to accommodate a hand wheel 17 for manual rotation of the rod, and a small drill 18 is provided in the other end and is secured in position by means of a setscrew 19. This rod is laid in the groove 8 with the end of the drill in engagement with the end of the carbon stick, and the hand wheel 17 disposed beyond the groove so that the drill may be manually actuated to bore the carbon.

After the carbon has been bored or drilled, the operator takes a short holder rod 20 having a screw extension 21 mounted in the one end by means of a screw 22 and threads this screw into the bored end of the carbon stick until the end of the carbon stick butts tightly against the end of the holder rod, thus forming a continuous sectional stick which can be mounted in the projector (not shown) in exactly the same manner as is a new carbon stick. By reworking and mounting the short sections as above described, nearly all of the short sticks of carbon can be utilized. All size (diameter) carbon is treated in exactly the same manner, it is merely necessary that the diameter of the holder matches the diameter of the carbon stick and the instant device accommodates all sizes without any adjustment other than the clamping means.

From the foregoing, it will be clearly obvious that I have perfected a very simple, practical and inexpensive means and method for preparing and utilizing short, unburned or broken lengths of carbon such as used in motion picture projecting machines.

What I claim is:

A method of salvaging a short length of carbon rod by providing an extension of the same diameter thereon so that they can be used in a projection machine holder comprising the steps of; boring an opening centrally in one end of the carbon rod; and threading into said opening a screw projecting from a metal holder of the same diameter as the carbon rod until the end wall of the holder abuts the end wall of the carbon rod in which the opening is bored.

References Cited in the file of this patent UNITED STATES PATENTS 1,273,588 Donelly July 23, 1918 2,119,334 Lefller May 31, 1938 2,364,150 Lowenstein Dec. 5, 1944 2,371,831 Leming Mar. 30, 1945 2,378,525 Abegg June 19, 1945 2,528,033 Clark Oct. 31, 1950 2,598,006 Marr May 27, 1952 2,631,360 Sanford Mar. 17, 1953 

